Hard bosses and poorly-designed bosses—there's a difference

So, I'm playing Chili Con Carnage on PSP for an upcoming review.  I won't spoil the details, but one thing I will say is that the final boss is stupidly hard. I blasted through the entire game in a little over a day, but I was stopped dead in my tracks at the final level.  I tried it six or eight times, made virtually no progress towards seeing credits, and I gave up.  Frustration and anger made me put the game aside before I smashed the hell out of my PSP.

I'm not proud of this. 

I'm the kind of player that takes great pride in finishing games, and I have no problem with putting in the effort, polishing up my skills, learning the tricks, or doing whatever it takes to see something through to the end. I've finished several hundred games in my career, but the ones that stick out in my mind are always the ones that didn't get done.  I know it may seem self-serving, but looking back it seems to me that any time I didn't finish a game, it was due more to poor design than lack of effort on my part.

I'm sure that particular viewpoint of mine seems biased, but for the sake of this blog I'm going with the premise that I'm not a whimpering weaksauce and that developers sometimes make big mistakes when it comes to bosses and endgame sequences.

I really don't understand why they do it.  I mean, seriously... what's the point? Having a boss that's significantly more difficult than the gameplay that preceded it, or a boss that somehow breaks the rules that have been established over the course of gameplay feels like a developer's spitting in my face. I've spent time with their game, I've paid for their product, and I've supported their efforts in the industry... why would they want to completely piss me off?

It's not that I think they do it on purpose, but sometimes their decisions seem like such monumental misjudgments or unbelievably bad choices that I can't understand how any self-respecting developer who cares about their customers and fans would do such a thing. Do they just assume that most players aren't even going to make it that far, so why bother testing?  Or is it perhaps that their testers are so good and so "in the groove" of whatever game they're working on that they develop superhuman powers far above what the average game player will be able to duplicate?

It's not like I want beating a game to be handed to me on a silver platter and I understand the value in feeling like something has been achieved, but I can't stand it when a project that's been interesting, fun, or otherwise worthwhile ends on a sour note with an unbeatable boss or an unwinnable situation and ruins the experience. As a developer, doesn't it make more sense to leave your players feeling like they had a worthwhile ride instead of making them feel irritated and pissed by poor balance, lack of savepoints, bad design or any other misguided attempt to make the final bits of the game "challenging"? 

Chili Con Carnage is the most recent example (and it's an otherwise decent game, really), but there've been a handful of others and feeling the hate and frustration of defeat never diminishes, even for someone like me who has played and completed so many. Silent Bomber, Trauma Center, I curse you. NES Ninja Gaiden... there's a special place in hell just for you. And Vexx—my wife still hates your guts.